Any future Supreme Court rulings on this issue might not include Justice John Paul Stevens. He's been talking openly about retirement and when he retires, it is possible that for the first time, there will be no Protestant justices on the court.

TOTENBERG: Jeffrey Shesol is the author of the critically acclaimed new book, "Supreme Power."

Mr. SHESOL: It's not something that is talked about in polite company - although I think privately, a lot of people remark about the surprising fact that there are, in fact, this many Catholics on the Supreme Court.

TOTENBERG: In all of American history, there have been just 12 Catholics on the court, and six of them are there now. Only seven Jews have ever served on the court, and two of them are there now. Depending on the Stevens replacement, there may be no Protestants left on the court at all in a majority Protestant nation where for decades and generations, all the justices were Protestant.

The first Catholic to serve was Chief Justice Roger Taney, historically famous for writing the Dred Scott decision upholding slavery. After he left, no Catholic was appointed for 30 years. But by the early 20th century, the nation settled into a pattern in which there was one seat on the court occupied by a Catholic and usually, one by a Jew. No one Jewish justice, however, served on the court between 1969 and '93.

Historically, Republicans have been the party of Protestants. But Protestant Republicans Reagan and both Bushes appointed five of the Catholics currently sitting on the court: Chief Justice Roberts and Justices Scalia, Kennedy, Thomas and Alito.

The sixth Catholic, Justice Sotomayor, was appointed by President Obama. As for the two Jews, Justices Ginsburg and Breyer, both were appointed by President Clinton.

As attention focuses on a potential replacement for Justice Stevens, the two leading contenders to succeed him are Jewish - Solicitor General Elena Kagan and Appeals Court Judge Merrick Garland - while another often-mentioned name, Michigan Governor Jennifer Granholm, is Catholic. Yes, there are some Protestants in the mix, too; among them, Federal Judge Diane Wood. But it remains a distinct possibility that when the dust settles and a new justice takes his or her seat, there will be no Protestants on the high court.

Does it matter? Should it matter? Should it be discussed in polite society?

Professor HENRY ABRAHAM (University of Virginia): It would certainly raise a lot of eyebrows.

TOTENBERG: Supreme Court historian Henry Abraham teaches at the University of Virginia.

Prof. ABRAHAM: I don't know whether it matters. Speaking idealistically, to me the only thing that matters is competence, quality, education, ability, morals, and so forth.

TOTENBERG: Princeton Provost Christopher Eisgruber, another court scholar, says all of the justices were appointed because of their constitutional views.

Mr. CHRISTOPHER EISGRUBER (Princeton Provost): I don't think any of them are allowing their religious views to trump their honest, sincere judgments about the Constitution. And I think it's also worth noting that we've had Catholics on the court on both sides of the abortion question.

TOTENBERG: That's true, but in the last quarter-century, Republican Protestant presidents have appointed conservative Catholics, in part because of their reliably conservative judicial views.

Notre Dame's Richard Garnett says that the real dividing line in the country is not between Catholic and Protestant.

Mr. RICHARD GARNETT (Notre Dame Law School): It's more the kind of religious versus secular divide. So for those Protestants in America for whom their faith is important, they can look to the court and say, well, we do see representation on the court of people like us people who take their religious faith and their religious traditions seriously. True, they're Roman Catholics -they're not Baptists or Methodists, like us - but they take their religious traditions seriously.

Professor MARK NOLL (Notre Dame University): Is it a rebuke that there might be no Protestants on the Supreme Court? Indirectly, I suspect it would be.

TOTENBERG: A rebuke, he says, in terms of what Protestant identity means, and that there wasn't a Protestant good enough to fill even a single Supreme Court seat.

Pepperdine Law School's Mark Scarberry, a self-described evangelical Protestant, says there should be no religious test for appointment.

Professor MARK SCARBERRY (Pepperdine Law School): But I don't think that that means that a president shouldn't pay at least some attention to religious diversity on the court. It does seem to me that when you have such a large part of the country that has a particular sort of religious worldview, if there is no one on the court who is able to understand that worldview in a sympathetic way, then that creates difficulties.

TOTENBERG: So is this a subject that a nominee should or could be asked about? Professor Abraham...

Prof. ABRAHAM: I think that all hell would break loose. I cannot imagine that being brought up openly. Covertly perhaps, in some ways. But it's a highly delicate problem.

TOTENBERG: Indeed, all hell did break loose during the Bush administration, when some Democrats asked a Bush appeals court nominee whether he could enforce abortion rights, even though he'd called Roe vs. Wade an abomination.

The Democrats who asked that question found themselves pilloried in TV and radio ads for being anti-Catholic - even the ones who were lifelong, observant Catholics.

Nina Totenberg, NPR News, Washington.

MONTAGNE: Go ahead, be our guest, track the Supreme Court's shifting religious balance over time. You can do it at npr.org.

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